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3 years ago

Which of the following is a chemical change?

Chemistry

1 answer:

monitta3 years ago

5 0

Answer: C: A burning candle

Explanation:

C is a Combustion reaction and this is a chemical change.

The rest are physical changed because they are only changing state.

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How many hydrogen atoms are in 8.80 mol of ammonium sulfide

vladimir1956 [14]

Assuming that the ammonium sulfide formula is (NH4)2S then you can see that there are 2 nitrogen, 8 hydrogen and 2 sulfur atoms for every ammonium sulfide. If the amount of ammonium sulfide is 8.9 moles, then the number of hydrogen atoms should be: 8/1 * 8.9 mol= 71.2 moles

6 0

4 years ago

Whick ions profuce similar colors in the flame tests?

arlik [135]

Ba2+ and Cu2+, and Sr2+ and Li+

5 0

3 years ago

Calculate the amount of ATP in kg that is turned over by a resting human every 24 hours. Assume that a typical human contains ~5

valentinak56 [21]

Answer:

The correct answer is 66.35 kilograms.

Explanation:

Based on the data given in the question, the energy consumed by the body of a human being is 50%. Based on the given data, the energy consumed in a day is 8000 kJ, 50 percent is the energy transfer efficiency. Thus, the consumption of total energy is 4000 kJ, and for the transformation of ADP to ATP, the energy involved is 30.6 kJ per mole.

Hence, the total ATP produced in the process is,

ATP = 4000 kJ / 30.6 kJ/mol

= 130.7189 mol.

Thus, with the energy transfer efficiency of 50 percent, the total moles of ATP produced is 130.7 mol.

The mass of ATP can be calculated by using the formula,

moles = mass/molecular mass

The molecular mass of ATP is 507.18 g per mol

Now by putting the values we get,

mass of ATP = 130.7189 mol * 507.18 g/mol

= 66298.011 g or 66.298 kg

It is mentioned that human comprise 50 g of ATP or 0.05 kg of ATP. Therefore, the sum of the available ATP will be.

= Total production of ATP + Total ATP available

= 66.298 kg + 0.05 kg

= 66.348 kg

Hence, the sum of the ATP that is turned over by a resting human in a day is 66.35 kg.

5 0

3 years ago

The law of conservation of mass states that mass is neither created nor destroyed during a chemical reaction. This can be gleane

GenaCL600 [577]

Answer : The total mass of oxygen gas released in the reaction will be, 12.8 grams

Explanation :

Law of conservation of mass : It states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.

This also means that total mass on the reactant side must be equal to the total mass on the product side.

The balanced chemical reaction will be,

$2MgO\rightarrow 2Mg+O_2$

According to the law of conservation of mass,

Total mass of reactant side = Total mass of product side

Total mass of $2MgO$ = Total mass of $2Mg+O_2$

or,

Total mass of $2MgO$ = Mass of $2Mg$ + Mass of $O_2$

As we are given :

Total mass of $MgO$ = 16.12 grams

The mass of $Mg$ = 9.72 grams

So,

Total mass of $2MgO$ = Mass of $2Mg$ + Mass of $O_2$

$2\times 16.12g=2\times 9.72g+\text{Mass of }O_2$

$\text{Mass of }O_2=32.24g-19.44g=12.8g$

Therefore, the total mass of oxygen gas released in the reaction will be, 12.8 grams

8 0

3 years ago

Now that you have the knowledge of the highest specific heat capacity and lowest porosity, which material would you choose to bu

Svet_ta [14]

Answer:

Now that you have the knowledge of the highest specific heat capacity and lowest porosity, which material would you choose to build Rover's new doghouse roof?

Oak has the highest heat capacity; therefore, oak can absorb a lot of heat without raising its temperature. This is good for very hot areas. Concrete has the lowest porosity so water will not leak through its pores and drip into the doghouse. This is good for rainy areas. However, clay is second on both lists and might be a good choice overall for hot and rainy weather conditions. Rover should be happy with this.

xXxAnimexXx

Have a great day!

7 0

3 years ago

Read 2 more answers